The X-ray Stellar Cycle of Proxima Cen
Abstract
Stellar cycles in fully convective M stars were generally thought to be impossible until a few years ago, when ~8 examples were discovered from analysis of ASAS photometric monitoring data. Proxima Cen (dM5.5) was one of those stars, and also had (limited) supporting evidence for a cycle from Swift observations in the X-ray and UV, where emission is more directly tied to magnetic activity cycles (in contrast to spot/plage countereffects in photometry) and displays much larger cycle amplitudes. With several additional years of data, now spanning 8 epochs over more than 12 years, we find that an ~8-year cycle is clearly apparent in both X-rays and the UVOT/W1 band, and provide an update on the previously suggested association of X-ray cycle amplitude with Rossby number.
- Publication:
-
AAS/High Energy Astrophysics Division
- Pub Date:
- September 2023
- Bibcode:
- 2023HEAD...2011664W